Segmented Hairpin Topology for Reduced Losses at High-Frequency Operations

Preci, Eraldo; Nuzzo, Stefano; Valente, Giorgio; Gerada, David; Barater, Davide; Degano, Michele; Buticchi, Giampaolo; Gerada, Chris

Abstract

Nowadays, one of the key challenges in transport electrification is the reduction of components’ size and weight. The electrical machine plays a relevant role in this regard. Designing machines with higher rotational speeds and excitation frequencies is one of the most effective solutions to increase power densities, but this comes at the cost of increased losses in cores and windings. This challenge is even more pronounced in preformed windings, such as hairpins, which enable higher slot fill factors and shorten manufacturing cycle times. In this work, an improved hairpin winding concept is proposed, aiming to minimize high-frequency losses while maintaining the benefits deriving from the implementation of hairpin windings onto electrical machines. Analytical and finite element models are first used to assess the high-frequency losses in the proposed winding concept, namely the segmented hairpin, proving the benefits compared to conventional layouts. Experimental tests are also performed on a number of motorettes comprising both conventional and proposed segmented hairpin configurations. Finally, these experimental results are compared against those collected from motorettes equipped with random windings, demonstrating the competitiveness of the segmented hairpin layout even at high-frequency operations.

Citation

Preci, E., Nuzzo, S., Valente, G., Gerada, D., Barater, D., Degano, M., Buticchi, G., & Gerada, C. (2022). Segmented Hairpin Topology for Reduced Losses at High-Frequency Operations. IEEE Transactions on Transportation Electrification, 8(1), 688-698. https://doi.org/10.1109/TTE.2021.3103821

• Journal Article Type: Article
• Acceptance Date: Jul 25, 2021
• Online Publication Date: Aug 10, 2021
• Publication Date: 2022-03
• Deposit Date: Nov 26, 2024
• Journal: IEEE Transactions on Transportation Electrification
• Electronic ISSN: 2332-7782
• Publisher: Institute of Electrical and Electronics Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 1
• Pages: 688-698
• DOI: https://doi.org/10.1109/TTE.2021.3103821
• Keywords: Electrical and Electronic Engineering; Energy Engineering and Power Technology; Transportation; Automotive Engineering
• Public URL: https://nottingham-repository.worktribe.com/output/7655206
• Publisher URL: https://ieeexplore.ieee.org/document/9509846